Institute of Psychology, Polish Academy of Sciences, Warsaw, Poland.
Sci Rep. 2021 May 13;11(1):10281. doi: 10.1038/s41598-021-89289-y.
This study examines the relationship between the change in size and change in complexity of well-known/familiarized objects and exploratory activity regulation in rats. In our experiment, the rats were exposed to three types of environmental novelty in a well-familiarized chamber: (1) addition of new tunnels to the chamber, (2) increased size of a familiarized tunnel, and (3) increased complexity of the existing tunnels. The animals responded to the addition of new tunnels with a significant behavioural shift involving increased exploration of the newly installed tunnels. This effect was stable across all three test trials. The rats exposed to a change in size of the familiar object initially reacted with a behavioural shift towards the enlarged tunnel but then re-focused on the unchanged one. There was also a significant increase in the frequency of moving between the zones of the chamber. The experimental group exposed to an increased complexity of familiar objects responded with a pronounced behavioural shift towards the complex tunnel and then slightly intensified their exploration of the unchanged one. A decrease was also observed in the frequency of moving between the zones of the chamber in the first and second test trials. In the effect size analysis, no differences were found in any of the three groups, which suggests that all manipulations had similar impact. The data obtained in this study supports the view that in rats, curiosity is at least two-dimensional: activational and cognitive. The activational aspect of curiosity may be explained by novelty-related arousal processes, while the cognitive processes are activated at longer time intervals in response to more complex stimulation. The validation of this hypothesis requires further research involving manipulations with a recently standardized protocol for measuring free exploration.
本研究考察了大小和熟悉物体复杂性变化与大鼠探索性活动调节之间的关系。在实验中，大鼠在一个熟悉的环境中暴露于三种类型的环境新颖性：（1）在腔室中添加新隧道，（2）增加熟悉隧道的大小，以及（3）增加现有隧道的复杂性。动物对新隧道的添加表现出显著的行为转变，涉及对新安装的隧道的增加探索。这种效应在所有三个测试试验中都是稳定的。暴露于熟悉物体大小变化的大鼠最初对扩大的隧道表现出行为转变，但随后重新关注未改变的隧道。腔室区域之间的移动频率也显著增加。暴露于熟悉物体复杂性增加的实验组对复杂隧道表现出明显的行为转变，然后略微加强了对未改变隧道的探索。腔室区域之间的移动频率在第一和第二测试试验中也观察到下降。在效应大小分析中，三个组中都没有发现差异，这表明所有操作都具有相似的影响。本研究获得的数据支持了这样一种观点，即在大鼠中，好奇心至少是二维的：激活和认知。好奇心的激活方面可以通过与新奇性相关的唤醒过程来解释，而认知过程在更长的时间间隔内被激活，以响应更复杂的刺激。这种假设的验证需要进一步的研究，涉及使用最近标准化的自由探索测量协议进行操作。
